I have a clearance problem with the WRX install in the Spyder. The right side merged part of the exhaust just touches the chassis and I need to change by only about 25mm. The merg is cast so I can't just cut and shut. What do people suggest for the new header. If I'm going to make a new one I might as well get the best design I can.
4 into1?, 1.5" at each head x 2" collector and a 2.5" up pipe?
Lets hear it!



[Edited on 21-4-2004 by speedster356]

Hi Peter

I was talking to my exhaust guy the other day about making headers for rexys, he said most people that fit larger headers complain of lack of low end torque.

1302Steve

I have seen quite a few non turbo exhaust manifolds cut and welded so I'm sur eyou could modify your existing one.
Just to add to what Steve was saying. People have also reported good gains from match porting the standard manifold ports to the heads. Not actually too much work and as you have the headers off it would be rude not to
Rich

This has cast merged sections so I would rather not have to cut and weld cast steel?. I could see what an NA EJ20 manifold is like as I think they are all carbon steel or S/S.
Hows the projects going Richard?
Rigoli Motorsport mentioned the 4:1 but not tube sizes.





[Edited on 25-3-2004 by speedster356]

I'm no expert but I would suggest that the headed be reasonable small, say 1.5inch to help keep the exhaust gas velosity up. I would not bother making equal length primaries as ther eis little in the way of gains. From the turbo I would recomend 3'' tubing as it really does make a differance from my experiance, I'd also make up a wastgate dump pipe from some 1'' that enters tha exhaust just before the cat. This really helps things out and as an added benifit you can flange it and put on a screamer pipe when you are racing (we all love flames ) The only downside to a system like this is that the car will sound like a council bus at idle but who cares at 8k

This site has good info on WRX tuning, including exhaust size
http://www.mrtrally.com.au/performance/ 

use steel pipe 40mm id (the same size as the ports)
use cast steel pipe bends (that match the pipe)
10 or 12mm plate cut out the shape of gaskets
for the flanges
this is just my opinion after talking to 3000 people
when i made my own

Another Picture!!

Hadn't thought about running it behind the engine (In my case, mid mounted) but that might be a goer. So you used sch10 pipe for the manifold?

Hi

Hotdog your system looks much nicer than the factory one, I guess it would also have better clearance as well.

1302Steve

I like the look of these, but you don't get that boxer note.




[Edited on 21-4-2004 by speedster356]

Hey hotdog - looks like we have another EJ20T powered beetle in the world. What year and how far through the conversion are you ?

not a beetle a buggy
give me 2 months to have it on the road
by the way i also said this 2 months ago

more pic

any questions
i think i could answer most subi problems
and know i even know how to post pics
which i have of most bits and piceis

Decided to build just the two merged sections under each head and pull the right one in about 40mm to clear the frame. The head porting is favouring the forward merg so this seems to be the best solution.
Now were are those 1.5" bends?

:beer

we wanna see more buggy PICS :>

Exhaust just about finished.





[Edited on 21-4-2004 by speedster356]